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Posted to issues@calcite.apache.org by "Jiatao Tao (Jira)" <ji...@apache.org> on 2020/08/07 02:42:00 UTC
[jira] [Comment Edited] (CALCITE-4160) Add configuration to retain
ORDER BY in sub-query
[ https://issues.apache.org/jira/browse/CALCITE-4160?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17172777#comment-17172777 ]
Jiatao Tao edited comment on CALCITE-4160 at 8/7/20, 2:41 AM:
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Hi [~zabetak], [~julianhyde]
In ByteDance, we use Calcite as the SQL layer(parser/validate/optimizer) to build a Federated Query System like google F1. So it needs to adapt to the various engines like Spark/Presto/ClickHouse.
Take Spark, for example, we need to use RelNode to construct DataFrame, and Spark allows sort in sub-query. Take other engines, we convert RelNode back to SQL, whether they can handle sort in sub-query is by themself, but the SQL should have this info.
In fact, Presto/ClickHouse support sort in sub-query too.
was (Author: aron.tao):
Hi [~zabetak], [~julianhyde]
In ByteDance, we use Calcite as the SQL layer(parser/validate/optimizer) to build a Federated Query System like google F1. So it needs to adapt to the various engines like Spark/Presto/ClickHouse.
Take Spark, for example, we need to use RelNode to construct DataFrame, and Spark allows sort in sub-query. Take other engines, we convert RelNode back to SQL, whether the can handle sort in sub-query is by themself, but the SQL should have this info.
In fact, Presto/ClickHouse support sort in sub-query too.
> Add configuration to retain ORDER BY in sub-query
> -------------------------------------------------
>
> Key: CALCITE-4160
> URL: https://issues.apache.org/jira/browse/CALCITE-4160
> Project: Calcite
> Issue Type: Improvement
> Components: core
> Reporter: Jiatao Tao
> Assignee: Jiatao Tao
> Priority: Minor
>
> Pre discussion see in
> https://issues.apache.org/jira/browse/CALCITE-2798
> https://issues.apache.org/jira/browse/CALCITE-3664
> IMO, we should at least provide a configuration about this. People use Calcite most for its optimizer, and this info users may care, How it executed is by the engine, but users should know this in the plan.
>
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